One conventional three-phase power converting apparatus is a below-described power converting apparatus for solar power generation which converts DC power fed from a solar battery into AC power with three-phase outputs and delivers this AC power to a three-phase power system to which the power converting apparatus is connected. This power converting apparatus includes three sets of half-bridge inverters, each including two switching devices connected in series, wherein each of the three sets of half-bridge inverters is configured to output a positive or negative voltage with a neutral point of capacitors connected to a DC input portion set at zero level and obtain a desired output waveform by performing pulse-width modulation (PWM) control operation (refer to Patent Document 1, for example).    Patent Document 1: Japanese Laid-open Patent Application No. 1987-42213